Wnt10b与骨形态发生蛋白9诱导间充质干细胞成骨分化的关系

目的研究Wnt10b与骨形态发生蛋白9(BMP9)诱导间充质干细胞(MSCs)骨向分化的关系,以及相关的分子机制。方法利用PCR、Western blot、组织化学染色等方法,检测BMP9对Wnt10b表达的影响,以及Wnt10b对BMP9诱导的成骨分化的影响。同时,通过定量PCR、Western blot、油红O染色、流式细胞术等,分析Wnt10b影响BMP9成骨分化诱导作用的可能机制。结果 Wnt10b在C3H10T1/2、C2C12、MEFs和MC3T3-E1细胞中均有表达,BMP9在C3H10T1/2细胞中上调Wnt10b的表达水平。Wnt10b增强BMP9在C3H10T1/2细胞中增加OCN蛋白水平和促进钙盐沉积的能力,沉默Wnt10b减弱BMP9的作用。Wnt10b并不改变BMP9对细胞周期的影响,但能增强BMP9诱导的Smad1/5/8磷酸化,沉默Wnt10b减弱BMP9对Smad1/5/8磷酸化的促进作用。此外,Wnt10b抑制BMP9在C3H10T1/2细胞中诱导的成脂分化,沉默Wnt10b则促进BMP9的成脂分化诱导作用。结论 Wnt10b可以促进BMP9诱导的MSCs骨向分化,这种作用可能与增强BMP/Smad信号转导有关。     

骨形态发生蛋白9诱导间充质干细胞骨向分化与Wnt11的关系

目的探讨骨形态发生蛋白9(BMP9)诱导干细胞骨向分化与Wnt11的关系及可能的分子机制。方法通过q PCR、组织化学染色及Western blot等方法,检测成骨分化相关标志物,以及BMP/Smad和p38 MAPK信号的变化;利用荧光素酶报告质粒,检测BMP/Smad信号的活性改变。结果BMP9增加C3H10T1/2细胞中碱性磷酸酶(ALP)活性、钙盐沉积、骨桥素(OPN)和Wnt11表达。Wnt11在C3H10T1/2、MEFs、MC3T3-E1和C2C12细胞中均有表达。在C3H10T1/2细胞中,Wnt11增强BMP9促进ALP活性、钙盐沉积、Runx-2和OPN表达的作用,以及BMP9对BMP/Smad报告质粒转录活性和Smad1/5/8磷酸化的促进作用;Wnt11还增强BMP9诱导p38 MAPK磷酸化的作用;抑制p38 MAPK则减弱BMP9诱导ALP活性、钙盐沉积及OPN表达的作用,但该效应能被Wnt11部分逆转。结论 BMP9在MSCs中能上调Wnt11表达。Wnt11能促进BMP9的骨向分化诱导作用,该作用可能与其增加BMP/Smad和p38 MAPK信号的活性有关。     

骨形态蛋白9诱导干细胞骨向分化与环氧酶-2及PI3K/Akt的关系研究

目的研究骨形态蛋白9(BMP9)诱导干细胞成骨分化过程中对PI3K/Akt信号的激活与环氧酶-2(COX-2)的关系。方法利用组织化学染色法、化学发光法或定量PCR检测碱性磷酸酶(ALP)的水平,Western blot检测骨桥素(OPN)、骨钙素(OCN)、COX-2、Akt1/2和磷酸化Akt1/2(pAkt1/2)水平,RT-PCR检测COX-2的表达,用免疫组化或免疫荧光分别检测COX-2的表达水平以及Akt1/2的磷酸化水平,用茜素红染色检测钙盐沉积。结果 BMP9在C2C12细胞中明显增加ALP活性,促进OPN和OCN表达以及钙盐沉积;BMP9对Akt1/2总蛋白无明显影响,能明显增加Akt1/2磷酸化水平,PI3K抑制剂呈浓度依赖性减弱BMP9诱导ALP活性增加。BMP9在C2C12细胞中促进COX-2表达,抑制COX-2明显减弱BMP9在C2C12细胞中诱导ALP活性增加和钙盐沉积的作用。外源性过表达COX-2促进BMP9诱导p-Akt1/2水平增加,而抑制COX-2则明显减弱BMP9诱导Akt1/2磷酸化水平增加。结论 BMP9在诱导干细胞成骨化过程中对PI3K/Akt信号的激活可能与其促进COX-2表达有关。     

美洛昔康对骨形态发生蛋白9诱导间充质干细胞骨向分化的抑制作用

目的 探讨美洛昔康对骨形态发生蛋白9(BMP 9)诱导间充质干细胞成骨分化的影响。方法 用BMP 9编码序列的重组腺病毒感染C3H10T1/2细胞,并同时加入美洛昔康5, 10和20 μmol·L^-1对BMP9的作用进行干预。采用化学发光法检测第5天、第7天和第9天的碱性磷酸酶(ALP)活性, RT-PCR方法分别于第9天和第11天检测骨钙蛋白mRNA表达以及第1天、第3天和第5天Dlx-5 mRNA表达, 于第14天和第20天采用茜素红S染色法检测钙盐沉积。另用荧光素酶报告质粒检测BMPR-Smad信号的转录活性。结果 与正常C3H10T1/2细胞组相比,第5~第9天BMP9组ALP活性明显增加(P<0.01),但加入美洛昔康5, 10和20 μmol·L^-1后,ALP活性随美洛昔康浓度增加而明显降低(P<0.05)。与正常C3H10T1/2细胞组相比,BMP9组骨钙蛋白素和Dlx-5 的mRNA表达水平及钙盐沉积明显增加,美洛昔康则明显抑制BMP9诱导的骨钙蛋白素和Dlx-5 mRNA的表达及钙盐沉积(P<0.05)。BMP9促进C3H10T1/2细胞中BMPR-Smad报告质粒的荧光素酶活性增加(P<0.01), 美洛昔康能够抑制BMP9对BMP-Smad信号的活化作用(P<0.05)。结论 美洛昔康对BMP9诱导的间充质干细胞成骨化有明显的抑制作用,其机制可能与抑制BMP-Smad信号激活有关。     

白细胞介素10对体外培养大鼠主动脉平滑肌细胞成骨样分化 与钙化的影响

目的 探究白细胞介素10(IL-10)对体外培养大鼠主动脉平滑肌细胞(VSMCs)成骨分化,钙化和可能的信号传导途径。方法 提取大鼠胸VSMCs,采用钙浓度测定,碱性磷酸酶(ALP)活性测定和茜素红染色观察IL-10对钙化的影响。实时聚合酶链反应(Real-Time PCR)探究IL-10对成骨样分化的作用;蛋白质免疫印迹(Western Blot)用于检测成骨分化蛋白,观察IL-10对高钙高磷诱导的VSMCs钙化的作用。结果 IL-10促进高钙高磷引起的VSMCs钙化,上调成骨分化标志物的表达,激活骨形态形成蛋白2/白细胞抑制因子1,5/Runt相关转录因子2通路(BMP2/Smad1,5/RUNX2),并且抑制活化T细胞核因子c1(NFATc1)的表达。结论 IL-10能够诱导VSMCs成骨样分化,这可能是临床上观察到IL-10与血管钙化相关的机制之一。IL-10这一作用与其激活BMP2/Smad1,5/RUNX2通路,抑制NFATc1激活有关。     

过表达组蛋白去甲基化酶Jmjd3对成骨分化的调控作用

目的 研究过表达组蛋白去甲基化酶Jmjd3对间充质干细胞成骨分化的调控作用.方法 建立通过骨形态发生蛋白-2(bone morphogenetic protein-2,BMP-2)诱导的间充质细胞系C3H10T1/2成骨分化模型;通过荧光定量PCR检测成骨分化转录因子,成骨细胞标记基因的表达;通过碱性磷酸酶活性测定其表达量;通过基因克隆构建Jmjd3的过表达载体,并转染到C3H10T1/2细胞实现过表达;通过免疫印迹方法鉴定蛋白质水平;通过荧光素酶报告基因测定Jmjd3对Runx2和Osx基因的转录调控.结果 BMP-2促进C3H10T1/2细胞内Jmjd3的表达;过表达Jmjd3促进碱性磷酸酶活性,以及成骨分化标记基因COLⅠ,Ocn,Bsp的表达;同时,过表达Jmjd3促进成骨转录因子基因Runx2和Osx的转录,进而促进其基因表达.结论 过表达组蛋白去甲基化酶Jmjd3对间充质干细胞的成骨分化有重要的正向促进作用.     

地塞米松诱导小鼠骨髓基质细胞成骨的分子机制

目的 研究骨髓间充质细胞成骨分化的分子机制，为将其作为基因治疗的载体细胞奠定理论基础。方法 取成年小鼠股骨骨髓，贴壁培养，分别用矿化诱导培养基（10^-7 M地塞米松、10mM β-甘油磷酸钠和50mg／ml抗坏血酸）与骨形成蛋白2诱导，用RT-PCR检测Runx2，Osx和骨钙蛋白基因表达，茜素红染色鉴定钙节结。结果 RT-PCR显示，矿化培养基诱导组仅有Osx和OCN表达，BMP2诱导组Runx2，Osx和OCN全部表达，而两组茜素红染色均呈阳性钙结节。结论 地塞米松诱导的成骨作用中可能通过不同于BMP2的信号通路起作用。     

白藜芦醇对LPS诱导的MC3T3-E1成骨细胞的骨保护作用

目的探讨白藜芦醇对脂多糖(LPS)诱导的MC3T3-E1成骨细胞的骨保护作用。方法采用CCK-8法检测白藜芦醇不同浓度下MC3T3-E1成骨细胞的细胞增殖活性,对硝基苯磷酸盐法检测白藜芦醇不同浓度下MC3T3-E1成骨细胞ALP活性。将MC3T3-E1成骨细胞分为空白组(基础培养基)、对照组(LPS 2μg/mL)和实验组(LPS 2μg/mL+白藜芦醇20μmol/L)。采用qRT-PCR检测三组成骨相关基因Runx2、ALP、骨钙素(OCN)和骨桥蛋白(OPN) mRNA表达,Western blot法检测三组细胞沉默调节蛋白1(SIRT1)蛋白表达。结果白藜芦醇20μmol/L是MC3T3-E1成骨细胞最适成骨浓度(P<0.05)。与空白组比较,实验组成骨相关基因Runx2、ALP、OCN和OPN mRNA表达水平和SIRT1蛋白表达水平均降低(P<0.05);与对照组相比,实验组成骨相关基因Runx2、ALP、OCN和OPN mRNA表达水平和SIRT1蛋白表达水平升高(P<0.05)。结论白藜芦醇能够通过提高Runx2、ALP、OCN、OPN和SIRT1相关...     

Smad6信号干扰对MSCs骨向分化的影响

目的研究Smad6信号干扰对骨形态发生蛋白2（BMP-2）诱导的骨髓间充质干细胞（MSCs）骨向分化的促进效应。方法培养小鼠MSCs,用BMP-2诱导骨向分化。细胞分为3组：A组细胞用携带绿色荧光蛋白（GFP）的Smad6重组RNA干扰载体转染;B组细胞用空白载体转染;C组细胞作为对照。结果病毒转染后GFP在MSCs中有效表达,病毒转染效率达98．5％。与B组比较,Smad6RNA干扰显著提高了A组细胞AIP活性和骨钙素水平（P〈0．01）,而C组ALP活性和骨钙素水平均显著低于其他2组（P〈0．01）。茜素红染色显示,A组矿化结节数目显著多于B组（P〈0．05）,而c组无矿化结节形成。结论Smad6RNA干扰可有效促进BMP-2诱导的MSCs骨向分化,该研究为骨组织工程中骨缺损修复提供了一个极具价值的手段。     

Quantitative in vivo and in vitro sex differences in artemisinin metabolism in rat

1. The pharmacokinetics of the antimalarial compound artemisinin were compared in the male and female Sprague-Dawley rat after single dose i.v. (20 mg.kg) or i.p. (50 mg.kg) administration of an emulsion formulation. 2. Plasma clearance of artemisinin was 12.0 (95% confidence interval: 10.4, 13.0) l.h. kg in the male rat and 10.6 (95% CI: 7.5, 15.0) l.h. kg in the female rat suggesting high hepatic extraction in combination with erythrocyte uptake or clearance. Artemisinin half-life was 0.5 h after both routes of administration in both sexes. Values for plasma clearance and half-lives did not statistically differ between the sexes. 3. After i.p. administration artemisinin AUCs were 2-fold higher in the female compared with male rat (p 0.001). Artemisinin disappearance was 3.9-fold greater in microsomes from male compared with female livers and it was inhibited in male microsomes by goat or rabbit serum containing antibodies against CYP2C11 and CYP3A2 but not CYP2B1 or CYP2E1. 4. The unbound fraction of artemisinin in plasma was lower (p 0.001) in plasma obtained from the male (8.8 2.0%) compared with the female rat (11.7 2.2%). 5. The possibility of a marked sex difference, dependent on the route of administration, has to be taken into account in the design and interpretation of toxicological studies of artemisinin in this species.     

Quantitative in vivo and in vitro sex differences in artemisinin metabolism in rat

1. The pharmacokinetics of the antimalarial compound artemisinin were compared in the male and female Sprague-Dawley rat after single dose i.v. (20 mg x kg(-1)) or i.p. (50 mg x kg(-1)) administration of an emulsion formulation. 2. Plasma clearance of artemisinin was 12.0 (95% confidence interval: 10.4, 13.0) 1 x h(-1) x kg(-1) in the male rat and 10.6 (95% CI: 7.5, 15.0) 1 x h(-1) x kg(-1) in the female rat suggesting high hepatic extraction in combination with erythrocyte uptake or clearance. Artemisinin half-life was approximately 0.5 h after both routes of administration in both sexes. Values for plasma clearance and half-lives did not statistically differ between the sexes. 3. After i.p. administration artemisinin AUCs were 2-fold higher in the female compared with male rat (p < 0.001). Artemisinin disappearance was 3.9-fold greater in microsomes from male compared with female livers and it was inhibited in male microsomes by goat or rabbit serum containing antibodies against CYP2C11 and CYP3A2 but not CYP2B1 or CYP2E1. 4. The unbound fraction of artemisinin in plasma was lower (p < 0.001) in plasma obtained from the male (8.8 +/- 2.0%) compared with the female rat (11.7 +/- 2.2%). 5. The possibility of a marked sex difference, dependent on the route of administration, has to be taken into account in the design and interpretation of toxicological studies of artemisinin in this species.     

Interindividual variability in metabolic activation in humans in vivo

In assessing interindividual variability in metabolic activation, the toxic metabolite is often too unstable for conventional analysis. Possible alternatives include a stable product of the reactive metabolite e.g. cysteinyl derivatives of N-acetyl-4-benzoquinoneimine, the toxic metabolite of paracetamol, adducts with DNA or protein, and indirect measurement of the activity of the enzyme(s) producing the active metabolite. An example of the last approach is the use of furafylline, a highly specific inhibitor of human CYP1A2, to determine the extent of the metabolic activation of the cooked food mutagens PhIP and MeIQx. The extent of inhibition, determined from levels of unchanged amine in urine, is an indirect measure of the activity of the activation pathway. Further refinement of this approach, allied to improved measures of the biological process of interest should prove of value in evaluating interindividual variability and its role in the risk assessment process.     

Theophylline kinetics in peripheral tissues in vivo in humans

Several biochemical and cellular effects have been described for methylxanthines under in vitro conditions. However, it is unknown, whether threshold concentrations required to exert these effects are attained in target tissues in vivo. We therefore employed the microdialysis technique for measuring theophylline concentrations in peripheral tissues under in vivo conditions.Following in vitro and in vivo calibration, microdialysis probes were inserted into the medial vastus muscle and into the periumbilical subcutaneous adipose layer of healthy volunteers. Following single oral dose administration of 300 mg or i.v. infusion of 240 mg theophylline, in vivo time courses of theophylline concentrations were monitored in tissues and plasma. Major pharmacokinetic parameters (c_max, t_max, AUC) were calculated for plasma and tissue time courses. The mean AUC_tissue /AUC_plasma-ratio was 0.56 (p.o.) and 0.55 (i.v.) for muscle and 0.55 (p.o.) and 0.72 (i.v.) for subcutaneous adipose tissue.We conclude that microdialysis provides important information on the distribution and the tissue pharmacokinetics of theophylline.Abbreviations FPIA Fluorescence polarisation immuno assay - AUC Area under the curve - t_max Time to peak concentration - c_max Peak concentration     

休克时血中氧自由基的变化

本实验测定10名休克患者血浆和红细胞的丙二醛(MDA)、血浆总抗的氧化活性(AOA)的含量。结果表明:休克病人红细胞膜和血浆 MDA 含量(4.298±0.722;5.348±0.834)与对照组(3.235±0.682;4.356±1.081)比较明显增高(P<0.05);血浆 AOA(39.65±7.858)与对照组(48.21±10.81)比较明显降低(P<0.01)。提示:休克时,患者机体内自由基反应增强是引起组织细胞损伤的原因之一。     

Changes in angiopoietin expression in glomeruli involved in glomerulosclerosis in rats with daunorubicin-induced nephrosis

AIM: To study the potential pathological role of endogenous angiopoietins in daunorubicin-induced progressive glomerulosclerosis in rats. METHODS: Seventy male Wistar rats were allocated randomly into a daunorubicin group (DRB; n=40) or a control group (n=30). The rats in the DRB group were injected with DRB (15 mg/kg), in their tails. Subsequently, at intervals of 1, 2, 4, 6, 8, and 12 weeks, 5 male Wistar rats in each group were chosen randomly for 24 h urinary protein quantitative measurements (24 h UPQM), and determination of plasma tumor necrosis factor alpha (TNF-alpha), angiopoietin-1 (Ang1), and angiopoietin-2 (Ang2) levels. Kidney sections were examined by electron microscopy, Periodic Acid Schiff (PAS) staining, immunohistochemical staining and in situ hybridization histochemistry. RESULTS: As glomerulosclerosis progressed in the DRB group, expression of Ang1 mRNA and protein in glomeruli decreased and expression of TNF-alpha protein, Ang2 mRNA and protein in glomeruli increased. Expression of Ang1 mRNA and protein in glomeruli were negatively correlated with 24 h UPQM, Fn protein expression, and mean area of extracellular matrix (MAECM). In comparison, expression of Ang2 mRNA and protein in glomeruli were positively correlated with 24 h UPQM, Fn protein expression and MAECM; furthermore, there was a positive correlation between plasma Ang2 and 24 h UPQM. Plasma TNF-alpha and expression of TNF-alpha in glomeruli were positively correlated with expression of Ang2 mRNA and protein in glomeruli. There was a negative correlation between Ang1 protein expression and Ang2 protein expression in glomeruli. CONCLUSION: During DRB-induced glomerulosclerosis, podocyte injury led to a shift in the balance of Ang1 and Ang2 in glomeruli. Increased TNF-alpha in plasma and glomeruli may upregulate Ang2 expression in glomeruli. Elevated Ang2 in both plasma and glomeruli may mediate protein permeability through the glomerular filtration barrier. Moreover, local expression of Ang2 may facilitate the progress of glomerulosclerosis by upregulating a component expression of extracellular matrix.     

Trichinellosis in immigrants in Switzerland

We describe a case of trichinellosis diagnosed at the Division of Infectious Diseases, Hospital of Lugano, in January 2009. This case was associated with a cluster of cases and was traced to the consumption of contaminated meat after a wild boar hunt in Bosnia.